The protective effect of peanuts, pine nuts and almonds on gastric intestinal metaplasia in Korean men

There are reports that nut consumption provides potential benefit for gastric pathologies including stomach cancer and Helicobacter pylori infection. However, there are no studies investigating the effect of nut consumption on gastric intestinal metaplasia (GIM). In a Korean cohort of 53 424 men (average age 38.7 ± 7.0 years) and 33 024 women (average age 38.0 ± 7.0 years), we analysed the risk of GIM according to the frequency of nut consumption (peanuts, pine nuts and almonds only) as the following: rare (<1 serving/month), ≤1 serving/month and <1 serving/week, ≤1 serving/week and <3 serving/week, ≤3 serving/week and <5 serving/week and ≥5 serving/week where one serving is 15 g. Cox proportional hazards model was used to calculate the multivariable-adjusted hazard ratio (HR) for GIM and their 95% confidence intervals (CI) in each group (adjusted HR [95% CI]). Subgroup analysis was conducted by body mass index (BMI, non-obesity <25 and obesity ≥25). The models were adjusted for age, regular exercise, BMI, smoking, alcohol intake (g/day), diabetes mellitus, hypertension, dietary fibre intake, sodium intake and total calorie intake. After 5.3 years (median 5.9 years) of follow-up, GIM was observed in 5073 subjects. In men, compared with rare nuts consumption, greater nuts consumption was associated with a lower risk of GIM (rare consumption: reference, 1/month-1/week: 0.85 [0.79-0.91], 1-3/week: 0.81 [0.72-0.91], 3-5/week: 0.70 [0.57-0.86] and ≥5/week: 0.59 [0.48-0.73]). Subgroup analysis indicated that the inverse relationship between nuts consumption and the risk of GIM is more distinct in men without obesity (rare consumption: reference, 1/month-1/week: 0.83 [0.76-0.91], 1-3/week: 0.78 [0.67-0.91], 3-5/week: 0.68 [0.51-0.89] and ≥5/week: 0.51 [0.37-0.69]). However, this association was not observed in women. In conclusion, increased nuts consumption was associated with a decreased risk of GIM in working aged Korean men.